The present invention generally relates to high-temperature plate-fin heat exchangers. Such heat exchangers may include a cold fluid pathway and a hot fluid pathway. The heat exchanger may be used to heat cold fluid (e.g., outside air) and/or cool hot fluid (e.g., cooling fluid from an engine). Plate-fin heat exchangers may operate with any combination of fluids (gas, liquid, or two-phase fluid). The hot fluid may include transient changes in temperature due to various operating conditions (e.g., increased heat from engine throttling).
Such transient changes in temperature create gradients throughout the heat exchanger that may cause degraded performance and/or operating life due to thermal fatigue of tube sheets with the heat exchanger. High-temperature heat exchangers may be especially susceptible to fatigue at the hot/hot corner (the corner at the hot inlet and cold outlet) and the hot/cold corner (the corner at the hot inlet and the cold inlet).
Accordingly, there is a need for a heat exchanger with improved resistance to thermal fatigue.
In one aspect of the present invention, a plate-fin heat exchanger adapted to reduce thermal fatigue, includes a cold fluid pathway running along a first axis, a hot fluid pathway running along a second axis perpendicular to the first axis, and at least one porous blocker bar running along the first axis, where the porous blocker bar includes a set of pores adapted to control flow along the hot fluid pathway and coupled to an inlet of the hot fluid pathway.
In another aspect of the present invention, a porous blocker bar adapted for use in a plate-fin heat exchanger includes a front face, a rear face, and multiple pores, each of the pores spanning from the front face to the rear face.
In yet another aspect of the present invention, a method of configuring a porous blocker bar for use in a plate-fin heat exchanger includes: receiving dimensional parameters, evaluating the received parameters, calculating design parameters at least partly based on the received parameters, and storing the calculated design parameters.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following drawings, description and claims.